I am having an issue where I want a value of my cookie to increase by 1 each time I load the page. Currently, I can get the value to go up by 1, but since the values variable is called at the beginning it continues to reset each visit.
var cName = "Cookie Value";
var cValue = 0, expDays = 10;
let cookies = document.cookie;
function buildCookie(cName, cValue, expDays) {
let date = new Date();
date.setTime(date.getTime() + (expDays * 24 * 60 * 60 * 1000));
const expires = "expires=" + date.toUTCString();
document.cookie = cName + "=" + cValue + "; " + expires + "; path=/";
}
function setToZero() {
buildCookie(cName, cValue=0, expDays);
console.log('Cookie set to 0');
}
function wholePackage() {
if (cookies == null) {
setToZero();
} else {
if (cValue >= 0) {
cValue = cValue + 1;
buildCookie(cName, cValue, expDays);
console.log('Cookie to set to ' + cValue);
}
}
}
wholePackage()
Any help would be appreciated, thank you.
The problem here is that you're resetting the counter on each page load because you don't read the current stored value inside of document.cookie.
You should first read the current value and then increment by 1.
In order to read the current value of a property inside the document.cookie you could do something like this:
const prop = document.cookie.split("; ").map(prop => prop.split("=")).find(prop => prop[0] === cName)
if (prop) {
console.log('Current counter:', prop[1])
}
The code is very naive, but it should give you a starting point.
If it's not clear please let me know.
In wholePackage methods you need to get value of cookie and convert it to number by below code:
+document.cookie.split("; ")[0].split("=")[1]
This is complete code:
var cName = "Cookie Value";
var cValue = 0, expDays = 10;
let cookies = document.cookie;
function buildCookie(cName, cValue, expDays) {
let date = new Date();
date.setTime(date.getTime() + (expDays * 24 * 60 * 60 * 1000));
const expires = "expires=" + date.toUTCString();
document.cookie = cName + "=" + cValue + "; " + expires + "; path=/";
}
function setToZero() {
buildCookie(cName, cValue = 0, expDays);
console.log('Cookie set to 0');
}
function wholePackage() {
if (!cookies) {
setToZero();
} else {
if (cValue >= 0) {
cValue = +document.cookie.split("; ")[0].split("=")[1] + 1;
buildCookie(cName, cValue, expDays);
console.log('Cookie to set to ' + cValue);
}
}
}
wholePackage()
If you want to set cookie value for each time page loads, then the initial value should be 1. Not zero. So, it is not setToZero, it should be setToOne. So set initial cValue = 1.
In the wholePackage function, you are checking if the cValue is greater than or equal to 0. If it's true you are setting the cookie to 0. Which is wrong in two way.
a. cValue is always 0 at the beginning. So it can't get higher.
b. Even somehow you manage to increase cValue (ex- using a database), it is still greater than 0 and making the cookie 0 again.
So, what you need is to check if the cookie exists. If cookie with the name cName exists it will be set to old cookie + 1. Otherwise set to zero.
You can't check cookie value with this code
cookies = document.cookie
Instead, write this function to check if cookie exists,
function getCookie(name) {
var dc = document.cookie;
var prefix = name + "=";
var begin = dc.indexOf("; " + prefix);
if (begin == -1) {
begin = dc.indexOf(prefix);
if (begin != 0) return null;
}
else
{
begin += 2;
var end = document.cookie.indexOf(";", begin);
if (end == -1) {
end = dc.length;
}
}
return decodeURI(dc.substring(begin + prefix.length, end));
}
Then the wholePackage function will be like this,
let cookies = getCookie(cName);
function wholePackage() {
if (cookies == null) {
setToOne();
} else {
cValue = cookies + 1;
buildCookie(cName, cValue, expDays);
console.log('Cookie to set to ' + cValue);
}
}
}
In buildCookie function, you can't have parameters' name as same as your previously declared variable. That's bad. cName, cValue is already declared in the beginning.
You don't need expiry date as a parameter as you are creating them inside the function.
Here is the complete fixed code,
var cName = "Cookie Value";
var cValue = 1;
function getCookie(name) {
var dc = document.cookie;
var prefix = name + "=";
var begin = dc.indexOf("; " + prefix);
if (begin == -1) {
begin = dc.indexOf(prefix);
if (begin != 0) return null;
}
else
{
begin += 2;
var end = document.cookie.indexOf(";", begin);
if (end == -1) {
end = dc.length;
}
}
return decodeURI(dc.substring(begin + prefix.length, end));
}
let cookies = getCookie(cName);
function buildCookie(cname, cvalue) {
let date = new Date();
date.setTime(date.getTime() + (expDays * 24 * 60 * 60 * 1000));
const expires = "expires=" + date.toUTCString();
document.cookie = cname + "=" + cvalue + "; " + expires + "; path=/";
}
function setToOne() {
buildCookie(cName, cValue);
console.log('Cookie set to 1');
}
function wholePackage() {
if (cookies == null) {
setToOne();
} else {
cValue = cookies + 1;
buildCookie(cName, cValue);
console.log('Cookie to set to ' + cValue);
}
}
}
wholePackage()
How do I set and unset a cookie using jQuery, for example create a cookie named test and set the value to 1?
Update April 2019
jQuery isn't needed for cookie reading/manipulation, so don't use the original answer below.
Go to https://github.com/js-cookie/js-cookie instead, and use the library there that doesn't depend on jQuery.
Basic examples:
// Set a cookie
Cookies.set('name', 'value');
// Read the cookie
Cookies.get('name') => // => 'value'
See the docs on github for details.
Before April 2019 (old)
See the plugin:
https://github.com/carhartl/jquery-cookie
You can then do:
$.cookie("test", 1);
To delete:
$.removeCookie("test");
Additionally, to set a timeout of a certain number of days (10 here) on the cookie:
$.cookie("test", 1, { expires : 10 });
If the expires option is omitted, then the cookie becomes a session cookie and is deleted when the browser exits.
To cover all the options:
$.cookie("test", 1, {
expires : 10, // Expires in 10 days
path : '/', // The value of the path attribute of the cookie
// (Default: path of page that created the cookie).
domain : 'jquery.com', // The value of the domain attribute of the cookie
// (Default: domain of page that created the cookie).
secure : true // If set to true the secure attribute of the cookie
// will be set and the cookie transmission will
// require a secure protocol (defaults to false).
});
To read back the value of the cookie:
var cookieValue = $.cookie("test");
UPDATE (April 2015):
As stated in the comments below, the team that worked on the original plugin has removed the jQuery dependency in a new project (https://github.com/js-cookie/js-cookie) which has the same functionality and general syntax as the jQuery version. Apparently the original plugin isn't going anywhere though.
There is no need to use jQuery particularly to manipulate cookies.
From QuirksMode (including escaping characters)
function createCookie(name, value, days) {
var expires;
if (days) {
var date = new Date();
date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
expires = "; expires=" + date.toGMTString();
} else {
expires = "";
}
document.cookie = encodeURIComponent(name) + "=" + encodeURIComponent(value) + expires + "; path=/";
}
function readCookie(name) {
var nameEQ = encodeURIComponent(name) + "=";
var ca = document.cookie.split(';');
for (var i = 0; i < ca.length; i++) {
var c = ca[i];
while (c.charAt(0) === ' ')
c = c.substring(1, c.length);
if (c.indexOf(nameEQ) === 0)
return decodeURIComponent(c.substring(nameEQ.length, c.length));
}
return null;
}
function eraseCookie(name) {
createCookie(name, "", -1);
}
Take a look at
How do I remove an existing class name and add a new one with jQuery and cookies?
<script type="text/javascript">
function setCookie(key, value, expiry) {
var expires = new Date();
expires.setTime(expires.getTime() + (expiry * 24 * 60 * 60 * 1000));
document.cookie = key + '=' + value + ';expires=' + expires.toUTCString();
}
function getCookie(key) {
var keyValue = document.cookie.match('(^|;) ?' + key + '=([^;]*)(;|$)');
return keyValue ? keyValue[2] : null;
}
function eraseCookie(key) {
var keyValue = getCookie(key);
setCookie(key, keyValue, '-1');
}
</script>
You can set the cookies as like
setCookie('test','1','1'); //(key,value,expiry in days)
You can get the cookies as like
getCookie('test');
And finally you can erase the cookies like this one
eraseCookie('test');
Hope it will helps to someone :)
EDIT:
If you want to set the cookie to all the path/page/directory then set path attribute to the cookie
function setCookie(key, value, expiry) {
var expires = new Date();
expires.setTime(expires.getTime() + (expiry * 24 * 60 * 60 * 1000));
document.cookie = key + '=' + value + ';path=/' + ';expires=' + expires.toUTCString();
}
Thanks,
vicky
You can use a plugin available here..
https://plugins.jquery.com/cookie/
and then to write a cookie do
$.cookie("test", 1);
to access the set cookie do
$.cookie("test");
Here is my global module I use -
var Cookie = {
Create: function (name, value, days) {
var expires = "";
if (days) {
var date = new Date();
date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
expires = "; expires=" + date.toGMTString();
}
document.cookie = name + "=" + value + expires + "; path=/";
},
Read: function (name) {
var nameEQ = name + "=";
var ca = document.cookie.split(";");
for (var i = 0; i < ca.length; i++) {
var c = ca[i];
while (c.charAt(0) == " ") c = c.substring(1, c.length);
if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length, c.length);
}
return null;
},
Erase: function (name) {
Cookie.create(name, "", -1);
}
};
Make sure not to do something like this:
var a = $.cookie("cart").split(",");
Then, if the cookie doesn't exist, the debugger will return some unhelpful message like ".cookie not a function".
Always declare first, then do the split after checking for null. Like this:
var a = $.cookie("cart");
if (a != null) {
var aa = a.split(",");
Here is how you set the cookie with JavaScript:
below code has been taken from https://www.w3schools.com/js/js_cookies.asp
function setCookie(cname, cvalue, exdays) {
var d = new Date();
d.setTime(d.getTime() + (exdays*24*60*60*1000));
var expires = "expires="+ d.toUTCString();
document.cookie = cname + "=" + cvalue + ";" + expires + ";path=/";
}
now you can get the cookie with below function:
function getCookie(cname) {
var name = cname + "=";
var decodedCookie = decodeURIComponent(document.cookie);
var ca = decodedCookie.split(';');
for(var i = 0; i <ca.length; i++) {
var c = ca[i];
while (c.charAt(0) == ' ') {
c = c.substring(1);
}
if (c.indexOf(name) == 0) {
return c.substring(name.length, c.length);
}
}
return "";
}
And finally this is how you check the cookie:
function checkCookie() {
var username = getCookie("username");
if (username != "") {
alert("Welcome again " + username);
} else {
username = prompt("Please enter your name:", "");
if (username != "" && username != null) {
setCookie("username", username, 365);
}
}
}
If you want to delete the cookie just set the expires parameter to a passed date:
document.cookie = "username=; expires=Thu, 01 Jan 1970 00:00:00 UTC; path=/;";
A simple example of set cookie in your browser:
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>jquery.cookie Test Suite</title>
<script src="jquery-1.9.0.min.js"></script>
<script src="jquery.cookie.js"></script>
<script src="JSON-js-master/json.js"></script>
<script src="JSON-js-master/json_parse.js"></script>
<script>
$(function() {
if ($.cookie('cookieStore')) {
var data=JSON.parse($.cookie("cookieStore"));
$('#name').text(data[0]);
$('#address').text(data[1]);
}
$('#submit').on('click', function(){
var storeData = new Array();
storeData[0] = $('#inputName').val();
storeData[1] = $('#inputAddress').val();
$.cookie("cookieStore", JSON.stringify(storeData));
var data=JSON.parse($.cookie("cookieStore"));
$('#name').text(data[0]);
$('#address').text(data[1]);
});
});
</script>
</head>
<body>
<label for="inputName">Name</label>
<br />
<input type="text" id="inputName">
<br />
<br />
<label for="inputAddress">Address</label>
<br />
<input type="text" id="inputAddress">
<br />
<br />
<input type="submit" id="submit" value="Submit" />
<hr>
<p id="name"></p>
<br />
<p id="address"></p>
<br />
<hr>
</body>
</html>
Simple just copy/paste and use this code for set your cookie.
You can use the library on Mozilla website here
You'll be able to set and get cookies like this
docCookies.setItem(name, value);
docCookies.getItem(name);
I think Fresher gave us nice way, but there is a mistake:
<script type="text/javascript">
function setCookie(key, value) {
var expires = new Date();
expires.setTime(expires.getTime() + (value * 24 * 60 * 60 * 1000));
document.cookie = key + '=' + value + ';expires=' + expires.toUTCString();
}
function getCookie(key) {
var keyValue = document.cookie.match('(^|;) ?' + key + '=([^;]*)(;|$)');
return keyValue ? keyValue[2] : null;
}
</script>
You should add "value" near getTime(); otherwise the cookie will expire immediately :)
Reducing the number of operations compared to previous answers, I use the following.
function setCookie(name, value, expiry) {
let d = new Date();
d.setTime(d.getTime() + (expiry*86400000));
document.cookie = name + "=" + value + ";" + "expires=" + d.toUTCString() + ";path=/";
}
function getCookie(name) {
let cookie = document.cookie.match('(^|;) ?' + name + '=([^;]*)(;|$)');
return cookie ? cookie[2] : null;
}
function eatCookie(name) {
setCookie(name, "", -1);
}
I thought Vignesh Pichamani's answer was the simplest and cleanest. Just adding to his the ability to set the number of days before expiration:
EDIT: also added 'never expires' option if no day number is set
function setCookie(key, value, days) {
var expires = new Date();
if (days) {
expires.setTime(expires.getTime() + (days * 24 * 60 * 60 * 1000));
document.cookie = key + '=' + value + ';expires=' + expires.toUTCString();
} else {
document.cookie = key + '=' + value + ';expires=Fri, 30 Dec 9999 23:59:59 GMT;';
}
}
function getCookie(key) {
var keyValue = document.cookie.match('(^|;) ?' + key + '=([^;]*)(;|$)');
return keyValue ? keyValue[2] : null;
}
Set the cookie:
setCookie('myData', 1, 30); // myData=1 for 30 days.
setCookie('myData', 1); // myData=1 'forever' (until the year 9999)
I know there are many great answers. Often, I only need to read cookies and I do not want to create overhead by loading additional libraries or defining functions.
Here is how to read cookies in one line of javascript. I found the answer in Guilherme Rodrigues' blog article:
('; '+document.cookie).split('; '+key+'=').pop().split(';').shift()
This reads the cookie named key, nice, clean and simple.
Try (doc here, SO snippet not works so run this one)
document.cookie = "test=1" // set
document.cookie = "test=1;max-age=0" // unset
Background
Cookies were originally invented by Netscape to give 'memory' to web servers and browsers. The HTTP protocol, which arranges for the transfer of web pages to your browser and browser requests for pages to servers, is state-less, which means that once the server has sent a page to a browser requesting it, it doesn't remember a thing about it. So if you come to the same web page a second, third, hundredth or millionth time, the server once again considers it the very first time you ever came there.
This can be annoying in a number of ways. The server cannot remember if you identified yourself when you want to access protected pages, it cannot remember your user preferences, it cannot remember anything. As soon as personalization was invented, this became a major problem.
Cookies were invented to solve this problem. There are other ways to solve it, but cookies are easy to maintain and very versatile.
How cookies work
A cookie is nothing but a small text file that's stored in your browser. It contains some data:
A name-value pair containing the actual data
An expiry date after which it is no longer valid
The domain and path of the server it should be sent to
Example
To set or unset cookies using Javascript, you can do the following:
// Cookies
function createCookie(name, value, days) {
if (days) {
var date = new Date();
date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
var expires = "; expires=" + date.toGMTString();
}
else var expires = "";
document.cookie = name + "=" + value + expires + "; path=/";
}
function readCookie(name) {
var nameEQ = name + "=";
var ca = document.cookie.split(';');
for (var i = 0; i < ca.length; i++) {
var c = ca[i];
while (c.charAt(0) == ' ') c = c.substring(1, c.length);
if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length, c.length);
}
return null;
}
function setCookie(name, days) {
createCookie(name, name, days);
}
function unsetCookie(name) {
createCookie(name, "", -1);
}
You can access like below,
setCookie("demo", 1); // to set new cookie
readCookie("demo"); // to retrive data from cookie
unsetCookie("demo"); // will unset that cookie
The following code will remove all cookies within the current domain and all trailing subdomains (www.some.sub.domain.com, .some.sub.domain.com, .sub.domain.com and so on.).
A single line vanilla JS version (no need for jQuery):
document.cookie.replace(/(?<=^|;).+?(?=\=|;|$)/g, name => location.hostname.split('.').reverse().reduce(domain => (domain=domain.replace(/^\.?[^.]+/, ''),document.cookie=`${name}=;max-age=0;path=/;domain=${domain}`,domain), location.hostname));
This is a readable version of this single line:
document.cookie.replace(
/(?<=^|;).+?(?=\=|;|$)/g,
name => location.hostname
.split(/\.(?=[^\.]+\.)/)
.reduceRight((acc, val, i, arr) => i ? arr[i]='.'+val+acc : (arr[i]='', arr), '')
.map(domain => document.cookie=`${name}=;max-age=0;path=/;domain=${domain}`)
);
I know, there are plenty of answers already, but here's one that has set, get, and delete all beautifully vanilla and nicely put into a global reference:
window.cookieMonster = window.cookieMonster ||
{
// https://stackoverflow.com/a/25490531/1028230
get: function (cookieName) {
var b = document.cookie.match('(^|;)\\s*' + cookieName + '\\s*=\\s*([^;]+)');
return b ? b.pop() : '';
},
delete: function (name) {
document.cookie = '{0}=; Path=/; Expires=Thu, 01 Jan 1970 00:00:01 GMT;'
.replace('{0}', name);
},
set: function (name, value) {
document.cookie =
'{0}={1};expires=Fri, 31 Dec 9999 23:59:59 GMT;path=/;SameSite=Lax'
.replace('{0}', name)
.replace('{1}', value);
}
};
Notice cookie getting regex was taken from this answer to a question in another castle.
And let's test:
cookieMonster.set('chocolate', 'yes please');
cookieMonster.set('sugar', 'that too');
console.log(cookieMonster.get('chocolate'));
console.log(document.cookie);
cookieMonster.delete('chocolate');
console.log(cookieMonster.get('chocolate'));
console.log(document.cookie);
If you didn't have any cookies before trying, should give you...
yes please
chocolate=yes please; sugar=that too
sugar=that too
Notice the cookies last not quite heat-death-of-the-universe long, but essentially that from our perspective. You can figure out how to change dates pretty easily from looking at the strings here or from other answers.
How to use it?
//To set a cookie
$.cookie('the_cookie', 'the_value');
//Create expiring cookie, 7 days from then:
$.cookie('the_cookie', 'the_value', { expires: 7 });
//Create expiring cookie, valid across entire page:
$.cookie('the_cookie', 'the_value', { expires: 7, path: '/' });
//Read cookie
$.cookie('the_cookie'); // => 'the_value'
$.cookie('not_existing'); // => null
//Delete cookie by passing null as value:
$.cookie('the_cookie', null);
// Creating cookie with all availabl options
$.cookie('myCookie2', 'myValue2', { expires: 7, path: '/', domain: 'example.com',
secure: true, raw: true });
Available Options:
expires: Define lifetime of the cookie. Value can be a Number (which will be interpreted as days from time of creation) or a Date object. If omitted, the cookie is a session cookie.
path: Define the path where cookie is valid. By default the path of the cookie is the path of the page where the cookie was created (standard browser behavior). If you want to make it available for instance across the entire page use path: '/'.
domain: Domain of page where the cookie was created.
secure: Default: false. If true, the cookie transmission requires a secure protocol (https).
raw: By default the cookie is encoded/decoded when creating/reading, using encodeURIComponent/ decodeURIComponent. Turn off by setting raw: true.
So I am new to JavaScript and I'm kinda stuck.
I want to allow my cookie to work on all of my pages.
I know that I need to add "/" to path. The only problem is that the little script I got is a bit different than all the examples out there.
Does somebody know where to put it?
var expdate = new Date();
expdate.setTime(expdate.getTime() + (24 * 60 * 60 * 1000 * 365));
function setCookie(name, value, expires, path, domain, secure) {
var thisCookie = name + "=" + escape(value) + ((expires) ? "; expires=" +
expires.toGMTString() : "") + ((path) ? "; path=" + path : "") + ((domain) ? ";domain=" + domain : "") + ((secure) ? "; secure" : "");
document.cookie = thisCookie;
}
function showCookie() {
alert(unescape(document.cookie));
}
function getCookieVal(offset) {
var endstr = document.cookie.indexOf(";", offset);
if (endstr == -1) endstr = document.cookie.length;
return unescape(document.cookie.substring(offset, endstr));
}
function GetCookie(name) {
var arg = name + "=";
var alen = arg.length;
var clen = document.cookie.length;
var i = 0;
while (i < clen) {
var j = i + alen;
if (document.cookie.substring(i, j) == arg) return getCookieVal(j);
i = document.cookie.indexOf(" ", i) + 1;
if (i === 0) break;
}
return null;
}
function MyNamer() {
var now = new Date();
now.setTime(now.getTime() + 365 * 24 * 60 * 60 * 1000);
var username = GetCookie("username");
if ((!username) || (username == 'null')) {
username = prompt("What is your name?:", "");
}
setCookie("username", username, now);
if (username) {
document.write(username);
setCookie("username", username, now);
} else
document.write("Guest")
}
Thanks in advance!
Well, from your code it looks like the 4th argument in setCookie is the one you want:
setCookie(name, value, expires, path, domain, secure)
e.g.setCookie("myCookie", "myCookieValue", new Date(), "/")
What are you using the cookie for? The webserver you're making the request from controls cookie data, including path. If you're just storing data then you could use the browsers' local/session storage objects?